1. Field of the Invention
The present invention relates to an object moving apparatus, and more particularly, to an object moving apparatus having a first motor, a second motor, a moving module and a controlling module. The controlling module selectively turns on the first motor or the second motor to drive the moving module.
2. Description of the Prior Art
In general, color printers can be classified into four major types: dot matrix printers, inkjet printers, laser printers and dye diffusion thermal printers. The dye diffusion thermal printer utilizes a thermal print head to heat ribbons containing dyes in order to transfer the dyes onto an object to be printed. In this way, continuous-tone can be formed on the object according to the heating time or the heating temperature. Due to its excellent printing quality and the natural, continuous color expression, the thermal printer is particularly suitable for photo printing applications.
In general, the dye diffusion thermal printer is capable of operating under a printing mode or a paper-moving mode since the dyes in respective ribbons with respective colors are transferred onto the object to be printed (e.g., paper). While operating under the printing mode, the dye diffusion thermal printer motor moves the object from an initial position to transfer dye of one specific color on the ribbon onto the object. Next, the dye diffusion thermal printer is switched to operate under the paper-moving mode. Under the paper-moving mode, the motor moves the object back to the initial position so as to transfer the dye of another specific color on the ribbon onto the object.
Please refer to FIG. 1. FIG. 1 is a diagram illustrating a typical dye diffusion thermal printer 100. As shown in FIG. 1, the dye diffusion thermal printer 100 comprises a stepping motor 110, an active pulley 122, a belt 124, a passive pulley 126, a capstan roller 132 and a pinch roller 134. The active pulley 122 is coupled to the stepping motor 110, the passive pulley 126 is coupled to the capstan roller 132, and the active pulley 122 and passive pulley 126 are coupled to each other via the belt 124. The power generated from the stepping motor 110 is therefore delivered to the capstan roller 132 through the active pulley 122, the belt 124 and the passive pulley 126 in sequence for rotating the capstan roller 132. Both the capstan roller 132 and the pinch roller 134 are in contact with a print media 10 (e.g., a piece of paper or a card). When the capstan roller 132 rotates, the pinch roller 134 is driven to rotate simultaneously to move the print media 10 together. The moving direction of the print media 10 depends on the rotating direction of the capstan roller 132. Taking FIG. 1 for example, when the capstan roller 132 rotates counterclockwise, the print media 10 is moved to the right (printing/paper-moving mode); otherwise, when the capstan roller 132 rotates clockwise, the print media 10 is moved to the left (paper-moving/printing mode).
To ensure a good print quality, the motor operating under the printing mode is expected to output with a high torque, and the motor operating under the paper-moving mode is expected to output at high speed. There is a fundamental trade-off, however, between torque and speed while the driving voltage is on the fixed level. More specifically, the motor can either output with a high torque but low speed or output with a high speed but low torque. As mentioned above, the prior art only uses one stepping motor to drive the capstan roller for rotating. With the traditional method, in order to make the stepping motor output with a high torque and high speed, high voltage or high current is required to drive the stepping motor. This method consumes high power, however. In addition, the volume of the stepping motor is also increased for the purpose of providing high speed and high torque. Furthermore, the temperature of the motor will get extremely high since the motor operates at the high power mode continuously.